Japanese Laid-open Patent Application No. 60-164157is a conventional heat pump hot-water supply apparatus, The heat pump hot-water supply apparatus (heat pump system) is capable of using heat pump cycle to heat water, and to feed the resulting warm water to the hot-water storage tank. More specifically, the heat pump system has a compressor, a condenser (usage-side heat exchanger), and an evaporator (heat-source-side heat exchanger), and is capable of heating water by heat radiation of the refrigerant in the refrigerant/water heat exchanger to obtain warm water.
Japanese Laid-open Patent Application No. 2003-314838is a heat pump-type warm water/air-warming apparatus. The heat pump-type warm water/air-warming apparatus (heat pump system) is capable of heating water using the heat pump cycle and carrying out air-warming operation (heating operation) by feeding the resulting warm water to a floor air-warming panel. More specifically, the heat pump system is composed of a warm-water supply unit (usage unit) having a refrigerant-to-water heat exchanger (usage-side heat exchanger), the warm-water supply unit being connected to an outdoor unit (heat source unit) having a compressor and evaporator (heat-source-side heat exchanger) via a refrigerant communication tube. With this heat pump system, water can be heated by heat radiation of a refrigerant in the usage-side heat exchanger to obtain warm water.